SlideShare a Scribd company logo
MongoNYC
‐
June
7
2011

Behind
the
Curtain
Signpost
‐
Who
are
we?

• AdWords
meets
Groupon
  ― LocaDon
Based
  ― Merchant
and
User
Contributed
Deals
  ― Decentralized
Sales
PlaKorm




                                          2
Who
am
I?

•   UDlity
Knife
Engineer
•   @maRnsler
•   hSp://github.com/maRnsler
•   hSp://www.maRnsler.com




                                3
Numbers

•   >
11M
Tracked
Requests
•   >
11M
Tracked
Events
•   4
Developers
•   2
Coffee
runs
/
Day




                             4
What
Makes
it
Work

• Websites
  ― Java
(Tomcat/Spring/MyBaDs),
MySQL,
Memcache
• AnalyDcs
  ― Java
(Tomcat/Cement/GuiceyMongo),
MongoDB,
Node.js




                                                         5
GuiceyMongo?
(A
liSle
shameless
self‐promoDon)

• Enables
MongoDB
Database/CollecDon
config
in
Guice
Injector
injector
=
Guice.createInjector(




GuiceyMongo.configure("TEST")








.mapDatabase("MAIN").to("test")








.mapCollection("USER").to("user").inDatabase("MAIN"),






GuiceyMongo.configure("PROD")








.mapDatabase("MAIN").to("prod")








.mapCollection("USER").to("user").inDatabase("MAIN"),






GuiceyMongo.chooseConfiguration("TEST")
);


@Inject
void
loadPerson(@GuiceyMongoCollection("person")
GuiceyCollection<Person>
personCollection)
{




Person
p
=
personCollection.findOne();




//
...
}




                                                                                                6
GuiceyMongo?

• Generates
Wrapper/Builder
code
from
a
simple
DDL
                            Person
p
=
personCollection.findOne();
                            System.out(p.getName());
                            System.out(StringUtil.join(p.getAliasSet(),
",
"));
                            if
(p.hasPicture())
{
                            



Image
picture
=
ImageIO.read(p.getPictureInputStream());
                            



//
do
something
with
the
picture
                            }
data   Person {

      string name;

      set<string> alias;

      blob picture;
}
                            Person.Builder
p
=
Person.newBuilder()
                            















.setName("Matt
Insler")
                            















.addAlias("Matt")
                            















.addAlias("Guice
&
Mongo
Guru")
                            















.setPictureBucket("pictures");
                            ImageIO.write(picture,
format,
p.getPictureOutputStream());
                            personCollection.save(p.build());




                                                                                    7
GuiceyMongo?

• Supports
embedded
complex
objects,
lists,
maps,
sets,
enums
data   Contact {                                          data   InstantMessenger {

      data Address {                                     
      enum Application {

      
    string street_1;                              
      
    AIM,

      
    string street_2;                              
      
    ICQ,

      
    string city;                                  
      
    Jabber,

      
    string state;                                 
      
    MSN,

      
    int zip_code;                                 
      
    Yahoo

      }                                                  
      }


      [identity]                                         
      string screen_name;

      string identity;                                   
      string alias;
                                                          
      IMApplication application;

      string first_name;                                 }

      string last_name;

      map<string, Address> address;

      map<string, string> phone_number;

      map<string, string> email_address;

      map<string, InstantMessenger> instant_messenger;

      set<string> tag;

      blob picture;
}




                                                                                              8
GuiceyMongo?

• Proxies
Server‐Side
Methods
(Stored
Procedures)
public
interface
ContactQuery
{




Contact
findContactByName(String
name);




List<Contact>
findContactsByIMAlias(String
alias);
}

Injector
injector
=
Guice.createInjector(








GuiceyMongo.configure("Test")












.mapDatabase("Main").to("test_db"),










GuiceyMongo.javascriptProxy(ContractQuery.class,
"Main"),










GuiceyMongo.chooseConfiguration("Test")
);


@Inject
void
exercise(ContactQuery
query)
{




query.findContactByName("Matt
Insler");
}




                                                                    9
Cement?

•   MVC
Framework
wriSen
for
Guice/MongoDB
•   Efficient
rouDng
and
built‐in
logging
and
excepDon
handling
•   Wrote
it
because
I
was
bored
and
I
could
•   Definitely
not
producDon‐ready
whatsoever




                                                                10
Enough
of
That

• On
to
the
meat
and
potatoes




                                11
We
Track
Everything

• Request
Tracking
• Event
Tracking
• ExcepDon
Tracking
/
Triage




                               12
We
Track
Everything

• Request
Tracking
• Event
Tracking
• ExcepDon
Tracking
/
Triage


Every Fat-Fingered Form Submission




                                     13
Request
Tracking

• Queued
and
wriSen
from
a
low‐priority
thread
from
Java
  ― WriSen
to
MySQL
first
  ― WriSen
to
MongoDB
with
MySQL
Primary
Key
for
differenDaDon
• Visitor
Key
‐
Cookied
browser/computer
• Session
Key
‐
Per
User
session
• Stripe
sessions
with
extra
informaDon
  ― acquisiDon/referrer
informaDon




                                                                14
AnalyDcs
Architecture
‐
Request
Tracking
Flow


Web                             MySQL


                               MongoDB


                                request




                                                15
Request
Tracking
‐
What
we
use
this
for

•   Spying
on
you
•   Customer
Service
•   UX
Analysis
•   Funnel
Analysis
•   ExcepDon
tracing
and
debugging




                                          16
User
AcDvity
‐
Visitor
Keys
(we’re
watching
you)




                                                   17
User
AcDvity
‐
Sessions
(we’re
watching
you)





                                                18
User
AcDvity
‐
Requests
(we’re
watching
you)




                                               19
Request
objects

{


"_id"
:
ObjectId("4de53548b09a6541874eb641"),


"method"
:
"GET",


"response_code"
:
200,


"parameters"
:
{




"raw"
:
"false",




"feedId"
:
"dealActivity",




"user‐opts"
:
"username,avatar",




"count"
:
"100",




"no‐cache"
:
"1306867013431",




"feedType"
:
"comment",




"userId"
:
"",




"targetUserId"
:
"",




"deal‐opts"
:
"id,location‐name,title,category",




"activity‐opts"
:
"id,user,type,rawtime,commentcontent",




"types"
:
"commenter",




"dealId"
:
"243844"


},


"user_agent"
:
"Mozilla/5.0
(Windows;
U;
Windows
NT
6.0;
en‐US;
rv:1.9.2.17)
Gecko/20110420
Firefox/
3.6.17
(.NET
CLR
3.5.30729)",


"referer"
:
"http://www.signpost.com/deals/Boston‐MA/Cafe‐Gigu/‐5‐for‐10‐Worth‐of‐Food‐at‐Cafe‐Gigu‐/
243844",


"visitor_key"
:
"6f6d7e229f2a06e6a0dcdac42b09b26d17dbfac2318be53bea72a996204e3731",


"uri"
:
"/api/recent‐activity",


"user_id"
:
null,


"session_key"
:
"008F75D5B7515B202DC1A610F9D86539",


"ip"
:
"123.28.156.46",


"response_time"
:
4,


"timestamp"
:
ISODate("2011‐05‐31T18:36:56.177Z")
}


                                                                                                          20
Request
Tracking
‐
Queries

• Visitor
Keys
by
User
db.request.mapReduce(function()
{


emit(this.visitor_key,
{start:
this.timestamp,
end:
this.timestamp});
},
function(key,
values)
{


return
{start:
values[0].start,
end:
values[values.length
‐
1].end};
},
{


query:
{user_id:
12345},


sort:
{timestamp:
1}
});



• Requests
by
Visitor
Key
db.request.find({visitor_key:
‘a3896b987c98d798e791432fff332’}).sort({create_time:
‐1});




                                                                                           21
We
Track
Everything

• Request
Tracking
• Event
Tracking
• ExcepDon
Tracking
/
Triage




                               22
Event
Tracking

• Queued
and
wriSen
from
a
low‐priority
thread
from
Java
  ― WriSen
to
MySQL
first
  ― WriSen
to
MongoDB
with
MySQL
Primary
Key
for
differenDaDon
• Events
are
wriSen
into
a
“raw”
collecDon
• Event
Fixer
process
normalizes
events
into
“fixed”
collecDon
  ― Drops
bot
traffic
  ― Accounts
for
historical
naming
changes
(user
||
userId
||
u
‐>
user_id)
  ― Converts
Strings
to
Numbers
if
necessary
for
later
indexing
• Event
Indexer
calculates
and
updates
“rollup”
collecDon




                                                                              23
AnalyDcs
Architecture
‐
Event
Flow


Web                             MySQL


                               MongoDB


                                event
BI
               Event Fixer
                                event.fixed
               Event Indexer



                                event.rollup


                                               24
Event
Tracking
‐
What
we
use
this
for

• Email
Funnel
Analysis
• Purchase/Signup
Funnels
• Counts
or
Sums
of
event
permutaDons
over
Dme
  ― We
aggregate
seconds,
minutes,
days,
weeks,
months,
years
• Top
Count/Sum
over
a
Dmeframe
  ― Such
as
top
5
deals
by
purchase
in
the
past
month




                                                                25
Event
Tracking
‐
Funnels

var
email_funnel
=
{


steps:
[{




type:
'event',




name:
'Unique
Emails
Sent',




output:
'length',




algorithm:
'distinct',




algorithm_data:
'event_properties.email_tracking_id',




query:
function()
{






var
query
=
{








event_name:
'email‐sent',








'event_properties.type':
'Daily
Deal',








create_time:
{}






};






query.create_time['$gte']
=
startDate;






query.create_time['$lt']
=
endDate;






return
query;




}


},
{




type:
'event',




name:
'Unique
Sessions
with
an
Email
Click',




output:
'length',




algorithm:
'distinct',




algorithm_data:
'session_key',




query:
{






event_name:
'email‐click',






'event_properties.email_tracking_id':
{$in:
'${data[0].data}'}




}


},
{




...


}]
};
execute_funnel(email_funnel);
                                                                       26
Event
Tracking
‐
What
we
use
this
for

• Email
Funnel
Analysis
• Purchase/Signup
Funnels
• Counts
or
Sums
of
event
permutaDons
over
Dme
  ― We
aggregate
seconds,
minutes,
days,
weeks,
months,
years
• Top
Count/Sum
over
a
Gmeframe
  ― Such
as
top
5
deals
by
purchase
in
the
past
month




                                                                27
Event
Tracking
‐
What
have
we
sold
lots
of?




          * Sorry, we can’t show you what these numbers actually are.
                                                                        28
Code?

function
sum_top_n_by_range(from,
to,
event,
property,
count)
{


var
r
=
db.event.rollup.mapReduce(function
()
{




emit(this.k[0].v,
this.c);


},
function
(k,
v)
{




var
s
=
0;




for
(var
i
in
v)
{






s
+=
v[i];




}




return
s;


},
{




query:
{e:
event,
s:
'day',
w:
{$gte:
from,
$lte:
to},
k:
{$size:
1},
'k.k':
property}


});


//
take
the
top
count
property_values


var
keys
=
r.find().sort({value:
‐1}).limit(count).map(function
(o)
{return
o._id;});


r.drop();


var
cursor
=
db.event.rollup.find({




e:
event,
s:
'hour',
w:
{$gte:from,
$lte:to},
k:
{$size:
1},




'k.k':
property,
'k.v':
{$in:
keys}


}).sort({w:
1});


var
result
=
{};


cursor.forEach(function(dataPoint)
{




//
organize
data
points
in
the
result
object
as
needed
by
your
output


});




return
result;
}




                                                                                             29
Event
Tracking
‐
MySQL

• Event
Table
+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+‐‐‐‐‐‐‐‐‐‐‐‐+
|
event_tracking_id
|
visitor_key






|
session_key


|
event_name
|
+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+‐‐‐‐‐‐‐‐‐‐‐‐+
|
















1
|
2928712...8447ac2
|
E2AEB...6E78C
|
dealClick

|
|
















2
|
30f3afc...72a504f
|
D16E7...C10DD
|
dealClick

|

• Event
Property
Table
+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+‐‐‐‐‐‐‐‐‐‐‐+‐‐‐‐‐‐‐‐‐‐‐‐‐+
|
event_tracking_property_id
|
event_tracking_id
|
event_key
|
event_value
|
+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐‐+‐‐‐‐‐‐‐‐‐‐‐+‐‐‐‐‐‐‐‐‐‐‐‐‐+
|

























1
|
















5
|
‘deal_id’
|



‘123887’
|
|

























2
|
















5
|



‘node’
|





‘web1’
|
|

























3
|
















5
|



‘algo’
|


‘default’
|




• Querying
is
hard
and
can
be
slow
• SlowQL



                                                                               30
Events
‐
New
Hotness

 {
 

"_id"
:
ObjectId("4de53c85c7d8327f56284f3a"),
 

"visitor_key"
:
"50f46d60e00efe0a17c42c7fffdc68bda530572d1f83972a83d6c61d684ba3ce",
 

"event_name"
:
"deal‐click",
 

"event_properties"
:
{
 



"ca"
:
"dl",
 



"deal_at_location_id"
:
98303,
 



"session_ca"
:
"dl",
 



"ct"
:
"?",
 



"cr"
:
"?",
 



"node"
:
"web2",
 



"bot"
:
"false",
 



"user_id"
:
163181,
 



"guest"
:
"true",
 



"session_cr"
:
"?",
 



"session_ct"
:
"?"
 

},
 

"session_key"
:
"1C9FA142A59465B745ECE2C1ACB15E62",
 

"timestamp"
:
ISODate("2011‐05‐31T19:07:48.533Z"),
 

"window"
:
{
 



"minute"
:
ISODate("2011‐05‐31T19:07:00Z"),
 



"hour"
:
ISODate("2011‐05‐31T19:00:00Z"),
 



"day"
:
ISODate("2011‐05‐31T00:00:00Z"),
 



"week"
:
ISODate("2011‐05‐30T00:00:00Z"),
 



"month"
:
ISODate("2011‐05‐01T00:00:00Z"),
 



"year"
:
ISODate("2011‐01‐01T00:00:00Z")
 

}
 }


                                                                                         31
Event
Rollups
‐
Can
you
say
finance
background?

{


"_id"
:
ObjectId("4de54041c7d8327f56285563"),


"c"
:
1,


"e"
:
"deal‐click",


"k"
:
[{




"k"
:
"deal_at_location_id",




"v"
:
245931


}],


"s"
:
"month",


"w"
:
ISODate("2011‐05‐01T00:00:00Z")
}



• Allows
for
many
permutaDons
and
drill‐downs
• Easy
to
add
new
tracking
aSributes,
just
by
adding
key/value

  pairs
• Easy
to
index
(queries
like
lightning)



                                                                  32
Tracking
Events
‐
Problems

• Rollups
taking
up
too
much
space
  ― Need
to
move
to
document
format
from
Kyle
Banker’s
“The
MongoDB

    Gamut:
Four
ApplicaDon
Designs”
  ― Tell
business
to
track
fewer
permutaDons?
(yea
right)
• Fixer
skipping
events
  ― Moved
from
{_id:
{$gt:
ObjectId(...)}}
to
{version:
{$lt:
5}}
• Fixer
running
slow
  ― Moved
from
findAndModify
to
find(...).limit(...)
and
then
update
in
bulk
  ― {version:
{$lt:
5}}
is
slower
than
{version:
{$lte:
4}}
!!!
• KEEP
INDEXES
IN
MEMORY!!!
  ― We
had
>
12G
indexes
on
a
7.5G
box



                                                                             33
We
Track
Everything

• Request
Tracking
• Event
Tracking
• ExcepGon
Tracking
/
Triage




                               34
ExcepDon
Tracking

• Special
events
in
the
event
tracking
collecDon




                                                   35
Full
Stack
Traces,
Permalinks,
Request
Context




                                                 36
Triage

• Group
excepDons
over
the
past
day,
week,
month




                                                   37
Make
Users
Happy!




                    38

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